Middle ear ventilation tube



FIG. 1 is a top perspective view of a middle ear ventilation tubeembodying the new design;

FIG. 2 is a bottom perspective view thereof;

FIG. 3 is a side elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a perspective view taken in the direction of the arrow 5 ofFIG. 3;

FIG. 6 is a top perspective view of a second embodiment of a middle earventilation tube embodying the new design;

FIG. 7 is an enlarged bottom perspective view of the embodiment of FIG.5; and

FIG. 8 is a side elevational view of the embodiment of FIG. 5.

The front elevational view of FIG. 4 and the perspective view of FIG. 5are also illustrative of the embodiment of FIGS. 6-8.

The ornamental design for a middle ear ventilation tube, substantiallyas shown and described.